Concrete expansion and contraction joint



Aug. 1,'1939. c. OLDER.

CONCRETE EXPANSION AND CONTRACTION JOINT Filed May 18, 1936 4 Sheets-Sheet 1 Aug. 1, 1939. c. OLDER CONCRETE EXPANSION AND'boNTRAcTIoN JoINT Filed My 18. 19:56

4 Sheets-Sheet 2 figg-@ .i0 Il 4 Sheets-Sheet 3 C. OLDER CONCRETE EXPANSION AND -CONI'RACTION JOINT Filed May 18, 1956 Z0] .ZZ

JOI j] h 1 IJ Aug'. 1, 1939.

` zo@ 710 109 J0@ f is! C. OLDER CONCRETE EXPANSION AND CONTRACTION JOINT Aug. 1, 1939.

Filed May 18, 19:56

4 Sheets-Sheet 4 w 6, A 1 r 1 Patented Aug. .1, 1939 'l PATENT OFFICE CONCRETE EXPANSION AND'4 JOINT 3 cunard oiaer, wimietie, ni.` Application May is, 19st, serial N. anaal.

13 claims;

One of the objects of the present invention is the provision of an improved expansion joint structure which is adapted to be shipped knocked down so that it may be assembled on the job with a minimum amount ot labor, and

adapted to meet varying conditions of installation.

Another object of the invention is the'provision of Ian improved expansion joint structure,

` the parts of which may be constructed of sheet 'metal so that the parts of ,the joint may be con'- structed by stamping-operations, thereby reducing the cost of the iinished joint.

Anotherlobject of the inventionv is the provii5 sion of an improved expansion joint which does not need to be assembled at the factory, and which includes detachable securing and supporting devices of an improved structure adapted to support the joint in-fassembled condition in the concrete form before the concrete is poured.'

Another object of the invention is the provision of an improved concrete expansion and contraction joint whichis adapted to be so assembled on the job that it may be used Ior construct- `gis-ing curved joints.

Another object of the invention is the provision of -an improved expansion and contraction joint structure the parts o fwhich are adaptedlto nest .with each other so that they may be more conveniently shipped in a -"knocked'down condition.

Other objects and advantages of the invention .A

will be apparent from the following description and the accompanying drawings, in which simi- ,35 lar characters of reference indicate similar parts throughout th several views.

Referring to the-three sheets oi.' drawings accompanying the specication, l i.

Fig. 1 is a viewin perspective of an assembled 4o joint structure for a contraction' joint, showing the vjoint as it appears, just before it is stak intoposition in the form on the ground;

Fig. 2 is a view in perspective of one form of end plate for closingthe crack at the end of the i5 concrete joint;

Fig. 3 is an elevationalgvie'w of the joint of n Fig. 1, with the end platev in proper position; v Fig. 4 is a vertical transverse sectional view of a joint constructed according to Fig. 1, shown iso" in connection with the concrete sections between which the contraction joint is formed; i Fig. 5 is a view similar to Fig. 4, of another modiiication, in whichmthe bottom of the expansion joint crack between the two concrete sec- 55 tions is closed by a sliding plate;

Fig. 6 is'a similar view of another modication, in which the bottom of the crack between the adjacent concrete sections is closed by means o of' afflexible seal;l

Fig 'i is a similar view of a modied form oi.' 5 construction, which is adapted to be used as an expansion joint as well as a contraction joint, in which the top of the crack is closed "by a exible seal; o. s Fig. 8 is a fragmentary view in perspective, 10 with the end of the joint in section, showing a modification of the expansion joint of Fig. 7 and utilizing a flexible seal at /the bottom of the air space between the concrete sections; 1

Fig. 9 isI another modified expansion joint, in 15 which the clamping members have been mddied to provide support for a sliding closure plate at the bottomV of the air space between the concrete sections; l Fig. `10 is a fragmentary sectional view of an- 20 other modification, in which the space between the ends of the clamping members at the bottom of the'concrete has been lled with acompressible .plasticl member 'to prevent concretev from getting in that space; j Fig. 11 is a viewsimilar toFig. 10 of another modification, in which thatv space between the ends of the clamping members at the bottom of the concrete has been filled by a collapsible metal bOX; 30

Fig. 12 is another modified form, inwhich the clampingmembers have been slidably connected with a telescoping member, and in which the .expansion joint pas iiexible sealing membersat the top and bot m; Fig. 13 is another modiiied expansion joint,

having provision for sliding movement on b oth sides of the joint and havinga' iiexlble seal for closing the top of the `air space between the concrete sections.

Fig. 14 is a view similar to Fig. 13of a modificaf tion which difiers from Fig. 13 in the provision of a sliding plate closure for the bottom of the y joint;

Fig. 15 is another modication of an' expan- 45 sion joint including premolded plastic asphalt members for spacing-the walls of an air cell, and utilizing my' clamping members with a sliding plate and exible sealing members at tho `top and bottom; 4 i

' Fig. 16 is another modincation similar to Fig. 15, in which the collapsible air `cell has been provided by means of two separate sheet metal boxes which are adapted to becollapsed when the concrete expands;

1'? is a fragmentary sectional view of another modification in which the clamping memtion 23.

bers have been provided with securing means for holding the collapsible or crushable iiller which is used initially to form the air space between the ends of the concrete sections;

Fig. 18 is a fragmentary plan view of an installation of an expansion joint constructedV according to the invention, such as that shown in Fig. 17, illustrating vthe use of short lengths to make a curved expansion joint;

Fig.y 19 is afragmentary elevational view of an expansion'joint assembly of the type of Fig. 17;

Fig. 20 is a view in Vperspective of the clamping and supporting member'used in the joint vof Eig. 1 i

Fig. 2i is a view in perspective of a continuous sheet metal socket for the sliding dowel plate.

Fig. 22 is a similar view of another modification embodying a still more simple division Iplate structure.

Referring 'to Figs. 1 to 4, these are views showing a contraction Joint constructed according to the present invention; III and II indicate the two adjacent sections of concrete, which are separated by the contraction joint,v which is indicated in its entirety by the numeral I2. f

The contraction joint preferably includes a continuous dowel plate I3, comprising a plate of sheet metal, such as steel, of substantially uniform thickness and width and of rectangular form. The dowel plate I3 is so arranged that it projects into both of the concrete-sections I0 and II, its center line being arranged along the line of the joint.

'I'he jointis preferably provided with apartlng plate I4, adapted to assure the formation of a crack midway between the edges of lthe dowel plate, I3, ,and the parting plate ll`may\consist of a plurality of relatively short sections I5, I3, I1 of parting plate stock. This parting plate stock may all be located on the same side of the dowel plate I3,or the sections I5-II may -be'arranged alternately on opposite sides or edges of the dowel plate I3. For example, each parting plate mayconsist of body flanges l'and I9, which are joined by a U-shaped fold 20, having a pair of parallel anges 2i, 22 joined by acurved por- The parallel .fiangeslIL 22 are spaced sumciently so that they may slidably receive the dowel plate I3, and the length of .the flanges 2|, 22 is suiiicientso that it will provide forfany possible amount of contraction of the concrete and still leave the dowel plate` I3 in the groove 24 of the parting plate I4.

The uncovered edge portion 2li ofthe dowel v.plate I3, which formsits own-groove in the concrete of the adjacent section II, is preferably greased 4so as to facilitate sliding between the dowel plate I3 and the concrete. As the concrete contracts, the dowel plate I Q slides in the groove 24 or in the concrete'groove at the opposite side of the dowel plate I3.

`The upper and lower flanges I3, I3 of the partingplate sections II-II may be held in alignment by clamping members 2|,"comprising U-shaped sheet metal clips winch are slipped over the top in notches 21, or I may dispense with the notches in other embodiments of the invention.

. yIn other.A embodiments of the invention, the

vangeswll and the flanges I3 may overlap each other, as shownat the right between'the sections I 6l and I1,in which case theparting plate may be provided in standard lengths and the lappingadjusted to accommodate the odd widow of rouiway without the vnecessity for changing any standard dimensions except the cutting of the dowel plate I3 to length. A

Fig. 1 shows a short section of the contraction joint as it looks when it is installed in the form before the concrete is poured, while Fig. 3 shows a section of the complete joint after the concrete has been poured and the installation is complete: The dowel plate I3- and parting plate Il are preferably supported by a plurality of supporting and clamping members 23, which may be identical inshape `and construction, but may be reversed in location. These clamping members also serve as anchoring memberssince the clamping, portions thereof become anchored in the concrete @n account of the shape of these parts.

Each of the clamping members 28 has a relatively long foot lange 23, which extends at right angles to the body iiange 32. The body ange 33 is long enough 'to support the parting plate I3 at the desired position, which is generally midway between the top and bottom surfaces of the ooncrete roadway, and it carries a horizontal supporting flange 3| at the top. This flange is bent back upon itself at 32, and is provided with a clamping iiangeI 33, which may curvev away from the ange 22 at the point 34, but curves downward into engagement with the flangeV 22 at the point 35.

. 'I'he clamping flange 33 at the point 3l is spaced from the flange 3i by an amount 'which is less than the distance between the outside surfaces of flanges 2| and L22 so that the clamping mem- `ber holds the i'ianges of the parting plate I4 in firm engagement with the dowel plate I3. This.

assures lack of unnecessary clearance'.y between' the dowel plate I3 and the guide fianges'of the parting plate I4, and is essential, since the dowel sembly then rests upon the foot flanges 23 and is held in place by the stakes 31.'

. top' of the pavement to the bottom.

It should be understood that the shape an in the diier'ent forms of construction of the joint,

and an appropriate end plate may be formed in any case by welding, riveting, or otherwise securing a suitablefi clamping member to an end plate 33.

Referring to Fig. 4, the complete installation preferably also includes a nexible sealing member 4U, which consists oi'-y flexible, non-corrodible sheet metal, such as copper. The sealing members used throughout ythe various modifications may take various difgent forms, many of which construction of the clamping members 23 varies I arealternatively usab'ie with any ofthe joints shown.

In this embodiment lthe sealing Amember has a exible bead 4|, which is carried by the two body flanges 42, 43, which extend vertically and arethemselves joined to anchoring ilanges 44, 45.

lThe'. anchoring flanges may have apertures forl anchoring in the concrete, ror they may have laterally bent ends or any other ty'peof anchore ing formation on the flanges 44, 45 to assure their securement in the concrete III and Il.

` 'Ihe vertical anges 42, 43 may be spaced sufliciently so that the metal seal 40 slidably engages the top of the contraction joint assembly, thereby assuring the support of the seal at the top` of thejoint. The concrete is customarily 'formed with a curved surface 44' leading downward to the seal 40, and the crack above'the seal may be filled with initially plastic filling 44", such as asphalt compound.

Referring to Fig. 5, this is a modification in which the joint has been provided with a sliding closure plate 46 of steel or other suitable material Vat the bottom. In order 'toaccommodate this closure plate, which is locatedat the bottoni` surface oi the concrete sections I5 and Mythe clamping members havev been made of different shape. They .may comprise members having the same element'spreviously described, but having an additional U shaped bend 41 o! the same shape las the clamping portion 5I, 32, 3l, 35,- previously described.

This clamping portion 41 is adapted to clamp the sliding closure plate 46, which is held between the oppositely disposed clamping portions 41, 48

of the oppositely disposed clamping and supporting members, each member of this type being indicated in its entirety by the numeral. y

The contraction joint oi.' Fig. 5 operates like that of Fig. 4 except that the plate 46 assures' .that the dirt of the subsoil will no t rise into the crack between the concrete sections lli and II. As the concrete contracts, sections l and'll draw away from each other and are kept in alignment with each other by the dowel plate li.

h The copper sealing member. at the top'is adapted to expand, each of its anchoring edges vbeing secured to one of the sections of concrete,

and it keeps the top of the crack inthe pavement closed and preventsing'ress of foreign material at' this point.

Referrngto Fig. 6, this-,is another modification,- in which the top andbottom of the contractionv joint l haveY been provided" with flexible copper sealing members 40, 50. g

In order to provide space for the lower copper sealing member V50, the clampingv member is l v members, 5|. 70=

formed with a semi-circular bend 52, which is of suilicent size to embrace the'sealing member 50, and which terminatesin the usual footilange 29.

This lower sealing memberj may be located in y between the bends 52 of the clamping members 5|, and it may-slidably engage the lower edge of the parting plate -|4.

In order to provide the lower copper sealing member 50 with `anchoring flanges 53 extending well into the concrete, these flanges may be provided with slots 54 for passing the clamping y Referring to Fig.

sion joint;tha't.is, a yjoint structureadapted for A- '.in'itial! expansion. -In this case the clamping members 55 and 56 are again of slightly different shape. The sliding dowel plate i3 may be the l J this is a modicationin- Vwhich-the invention is embodied in an expansame as previously described, and it is engaged on the right side by the clamping member 56, which is'substantially similar in construction to the clamping member 26, previously described,

except that the foot iiange 51 ,extends in the opposite direction under the concrete section 'l I, Awhere it is secured to the ground by a stake 58.v It diiers also inthe provision of an upward extension iiange 56, which is adapted to engage former being located above `the sliding dowel .I

plate I3, and the latter below it. These filler strips are suillcient in width to .permit the desired amount of expansion of the concrete sections and the thickness depends upon th distance between the expansion joints in a pavement.

. The filler strips are held in place between the vertical body ilanges oi the clamping membersI 55,' 56 and the extensions 59 of theseclamping members. which in turn are secured by the stakes The clamping melnber 55 differs `from the clamping member 56 in that its U shaped bend 52 is composed of two substantially parallel walls,r lwhich are longer than that portion of the dowel -plate which is located between them, thus leavy ing a space 63, into which the dowel plate may move when the concrete expands.

The sheet metal socket member B4 diil'ers from the sheet metal socket member 20, previously described, in .that it is .provided with parallel walls which are wider than the width of that part of the dowel plate i3 located between them, thereby providing the space 63 for the dowel plate I3. AIn this embodiment the expansion joint has been provided with a flexible copper sealing member 55, the top of which is 'of substantailly U shape, having a pair of parallel walls 66, 61

joined by a cylindrical portion 66, and terminating in the anchoring anges 69 which arean -choredy in the concrete sections I0, I I. rIl'he walls V65, 61 are spaced sumciently so that the copper seal is slidably mounted on thetop of the crushable vller 6l, so that the who'le assembly may' be supported by the feet 51.1

Referring to Fig. 8, thisjs a modification in which the expansion joint of Fig. 7 has been provided with..a ilexible copper'seaiing member 10, similar to the sealing member 65 used at the top in Fig. 7. It is slidably mounted on the lower 'edge of the lower crushable filler member 6|,

space being provided between the clamping mem bers 55 and 56 and the filler 6|. f

Thev anchoring flanges 1|,12,are provided with slots 13 wherever the clamping members 55, 56

are located so that the anchoring flanges 'may extend into the concrete to be. embeddedA therein.

In this case the supporting foot flanges 14 e'x- 'tend in opposite directions. Therefore, the

clampingmember 55, whichis anchored in the concrete section I0, has its foot flange t4 extending toward the other section.

In order to assurethe fact that the concrete willi'n'ot interfere with the movement oi the foot flanges 14 toward the opposite concrete section, each of these foot flanges is preferably provided with a,sliding cap 15. comprising a'sheet metal member of box-like form, open at one end, and

. of a suitable size to slide on the foot flange 1l.

Such sliding caps are preferably always employed on expansion joints where the foot flange of a clamping member which is anchored in one section extends into the opposite section. The edge of the dowel plate Il which projects-into the concrete section II may be oiled so as to permit sliding movement between the concrete and this part of the dowel plate. v

Referringto Fig. 9, this is a modification oi the expansion joint in which it is provided with a sliding closure plate 16 Aat the bottom. The lower section oi' crushable filler OI rests upon the closure plate 16. The clamping members 11, 18 are identical in construction at the top to the clamping members Si, 5B, just described with respect to Fig.- 7. At the bottom, however,

they are provided with additional clamping fo- It should be noted that wherever the' clamp' ing members 55, 56 or 11, 18 engage the closure plates 18 or dowel plate I3 directly, the parallel clamping ilanges are closer together than ,where the sheet metal of such a continuous socket member is interposed between the plate and the f clamping member.

' The engagement of the clamping members with the plates Il and 18 holds' all the parts together,

the vertical flanges oi the clampingmembers engaging the crushable fillers 0,' 6I. If 'desired, additional securement may be provided by stakes II which pass' through apertures l2 in that portion of the dowel plate I8 and closure' plate 10 which is embedded in the concrete section I I. This would fix the dowel plate Il and closure plate 16 to the right section II, permitting sliding movementonly at the opposite side into the spaces Il.

The lowermost flanges of the clampingjrnem-A bers'11, 1l serve -as ioot flanges Il, Il, and they,

are preferably beveled as at '85, so thatxwhen the concreteA expands, any` cementwhich hasv penetrated to the space II between the ends of these anges will be cut oi! from the plate 1l so that it cannot interfere with themovement of the foot anges 0I, ,Il toward each other.

Referring to Fig. 10, this is vanother modincation of the structure of the expansion'joint of Fig. 9, in which the foot flanges I3, Il have vnot been.beveled, but the space between them has been' filled with an initially plastic or crushable f ller strip I1 to assure absence o! concrete bei' tween these/end` flanges. a

Referring to Fig. 11, this is another fragmentary view of a modified bottoml structure` for the joint o f Fig. 9, in which ythe space has been filled by a .crushable sheet metal box 81, the top flange of which has a securing flange extension ll-that is held between the foot flange Il and the closure plate 1t. v Referring back to Fig. 9, this expansion joint has another type of iieible copper sealing member Il, which hasy two parallei upwardly` extending mais Il, n spaced smciently to be siidsbly engaged on the upper crushable filler strip Il.

Walls II, l2 have laterally projecting anchoring flanges which may be aperturedvor bent, or otherwise shaped to provide anchoring formations. VAt the top of walls 8|, I2 there is a pairof beads u, 95 which support a pair of downwardly'extending walls 96. l1, joined together by a ilat bottom wall Il, which rests on the top of filler strip il. The usual semi-plastic lling 8l. is located -in the groove between the walls 96, l1, and the expanslon of the strip 90 takes place at (the lower bends on each side of the flat bottom `S8. The beads 94, $5 are ordinarily anchored in the concrete IIIand II, but extraordinary contraction of the concrete` may draw them out and permit still further expansion. L A y Referring Fig. 12, this is another modification of the expansion joint of Fig. 9,' in which the joint is formed with Ya flexible copper sealing member |00 at the bottom, as well' as at^ the top III.

l In this case theclamping members III, III are of different shape at the bottom, but the upper portions are of the'same shape as those described in respect to Figs. 7 and 9.. At the bottom each clamping member has a flange I which extends away from the joint, and which is located Just above the anchoring flange ofthe copper seal 80 A downwardly extending flange Il!` on the clamping member I'III extends to the bottom of the concrete, arid a foot flange I extends over toward the crack between the oncrete sections I0 and H,'terminating flush wi h the face of the concrete i'ace Il1A of the concrete'section.

Thus, sulcient space is provided between the clamping members ifor the flexible seal IIII, which is of such shape that it slidably engages th lower edge of the lower crushable filling memberfth It should be noted that these copper sealing members have the usual anchoring flanges embedded in the concrete, and the flexible portion between the vertical flanges ofn the sealing members Ill. IIII comprises a plurality of bends or corrugations III, f

Two foot flanges Il! may be joinedby a relatively stiff metal telescopingftube IOL-which is.

of rectangularv shape in cross section so as to slidably engage the ends ofthe straps which comprise the foot ilanges Il' of the clamping mem-c bers IM, IIS. This telescoping tube may have a' frictional engagement with the foot flanges, thereby siding and holding the assembly together, and also assuring that there will be 'a space III between the endsl f-the foot flanges so that ex' pension oi' the co crete and movement of the ioot danses toward each other is permitted. Referring to Fig. 13, this is another modification, 'in which both edges of the sliding dowel plate I3 are provided with the continuous sheet metal socket members IH, H2, similar in con- ,struction to the socket member 84 described in Fig. 7. The socket members I II, II2 have a space III at each side, into which the dowel plate I3 may slide, and they are engaged by the'clamping 'members Ill, IIS. -y Here the clamping members may be oi' a shape substantially similar to the clamping member Il shown in Fig."1, which has suilicient space` in its clamping formationto/accommodate the enlargedcontinuous metal socket i membersl III, H2.

' ing member lit.

lar to clamping members 11 of Fig. 9, and the bottom of the joint diiers from that `of Fig. 1'3 in being provided with the sliding closure plate 16. The continuous sheet metal socket members 64 an'd 80 for the dowel plate I3 and closure plate 16 are used on both sides.

Referring back to Figs. .5 and 6, it will be noted that each length `of the division plate in Fig. 5 is made in" two sections. -The upper section comprises the vertical flangell.' the horizontal `flange |I1, and a vertical ilange H0. The lower section comprises the vertical iiange ||0, horizontal ange |20, and vertical flange |2|. In such case, the two pieces of which the complete division plate is made, are identical in shape and maybe more conveniently nested, s that they can be shippedin a "knocked down" condition.

It should be understood that any of the continuous sockets which have been described in respect to any of the modifications herein may either be constructed, as shown in Fig. 5, in two pieces', withoverlapping flanges ||8, H9, or, as shown in Fig. 14 at 64. in one piece. l Referring to Fig. 15, this is another modification, which utilizes'clamping members |22 o f similar shape, but oppositely disposed. These clamping members are similar at the top to the clampling formation B2 of clamping member 55 (Fig. '7) in that' they provide .additional space 63. At the bottom they are vsimilar to the lower` part oi clamping members 5| (Fig. 6) in that they curve inwardly at l23 and are provided with oppositely extending foot hangeslu having the cap memlbers 'it of Fig. 8. The curved portions |23 in this case are large enough to provide space ior a larger type of copper sealing member |26. The continu.- ous metal socket members |26, lill for the sliding dowel plate it are identical in shape and provide a space titi at eachV edge oi the dowel plate lli. Theyare provided with vertical body danses lid, iii! above and below of sumcieu't width to deune the air space lit between the ends oi the concrete sections it and Illl. They are spaced from each other at the middle by the initially plasticrpremolded strips it oi' asphalt compound, and at the top and bottom by the copper seal- These copper sealing members have the usual anchoring flanges itz and have upwardly extendingv anges ltd at each side. vthey have a hair-pin bead i3d above the edge of each wall |20, anda pair oi downwardly extending ianges i325' joined by a bottom portion ist.

The strips i311 may be held by prongs in hannes clamping members are similar to the clampix'igtj member 55 of Fig. B, dispensing with the curved portions |23 of Fig. 15. Y M

In order to accommodate the anchoring anges |32 lo1 the lower' copper 'sealing member |25, these iianges are provided with slots at |31, wherever the clamping members are; employed. The clamping members are staggered with respect to each other and regularly spaced along the joint in all modifications where the feet extend in opposite directions, asshown ih'Flg. 16.l In this case the continuous metaisoket members 64 l Fig. 7, and the air space llilbetween the ends of the concrete sections I0 and is formed by a pair of sheet metal box members |38, |39. These sheet metal box members each have a. pair oi vertical anges |40, |4|- which extend from the seal to the dowel plate ll. The)r are joined by an inwardly curved bottom |42 in thecas'e of the upper member |30, the initial curvature at |42 being for the purpose of facilitating the crushing oi' the box |30 or |39 when the concrete expands. 'I'he foot flanges 14 have the sliding metalcap 15. Referring again to Vthe danger of the core plates |40, 4| cuttingthe bend of the=seal |25, the plates |40, |4| may have their edges terminate short of the bends in the seal.Y The seal may have ribs |60 projecting outside the edges of plates |40, I4

and initially spacing these edges from the seal Referring to Fig. 17, this one of the preferred 'forms of the invention, and therefore will bedescribed in detail. Itcomprises the-crushable fiiling members 60, 0| and improved clamping members |43, |44. These clamping members areY identical .in constructi n, thereby necessitating the making oi.' only on type of clamping member, and they are provided with foot flanges |45.

The foot tlanges support the standards |45 which arelbent laterally at i411 andagain upwardly at Mt. The clamping member is bent lateraliyagain to form the ange im, which. is spaced from the flange Ml by a distance less than the thickness oi the composite members which it is intended to clamp. l g

Flange ldd supports a vertical flange |550, which is provided with inwardly extendingprongs itil and inwardly turned end harige iti engaging the crushable hller tt. lProngs loi may also be struck out oi the vertical harige ist to engage the lower crushable hller section di.

'The assembly is held in place by stakes let passing through apertures itt in the root anges idd, and the usual dowei plate i3 is covered at both edges with the continuous sheet metal socket member td.

The horrible copper seal itl is used at the andcovered with an initially plastic hller |50. Irllhe continuous sheet metal curves for thev dowel plate provide an expansion space t3 at both edges oi' the plate. The joint may be shipped ina knocked down condition and assembled on the lob. The clamping member |4313 shown in detail are similar. to those. shown in Fig. I4 and@ top I in perspective view in Fig. 20.l The joint is shown l not only the foot flanges |45 but to.press the op, postte clamping members toward each other by driving them asshown-in Fig. 17 with the stake in engagement with the yoke |41 of the clamp-f ing member, and passing through Athe apertures |55.

The lengths may be several feet inlength upy to several yards in length, depending upon the amount 'of curvature desired. By 'assembling such short lengths at the'job, as shown' in Fig. 18, an expansion Joint of any curvature may be made The stakes |54 oi' Fig. 17 may be made to secure The clamping members are preferably madel quite wide, that is, wider than necessary to clamp the socket members or dowel plate firmly, as these clamping members may serve to close the spaces between the dowel plates and continuous socket plates when the ends of the short lengths of'these plates do` not abut against each other squarely. as on a curve', or when it is desirable to space them to widen the roadway. For example, suppose the clamping members are three or four inches in width, and seven clamps are used on a joint for a roadway. By spacing the short lengths y of dowel plate and short lengths of division plates or continuous socket plates and usingrthe clamping members at each juncture of the plates, the wide clamps can be used to span the crackin the socket plates or the crack in the dowel plates wherever a socket lplate may notbe used.

By means of seven clamps an 4inch or mere may be gained on each clamp, and thus the road.- way may be made from seven to fourteen inches wider without the necessity for using any special lengths or parts. If desired, extra wide clamps may also be. provided for this purpose, differing from the standard clamps only in the matter of n should be noted that discontinuous socket plates for the dowel plates, which are in the na.

ture of a, shield for providing a suitable socketf of foreign material betweeny the cracks at the 'apart from the other parts of the joint, or any of the joints described herein may be used withouta exible seal. I advocate the use of a flexible seal or some other means of preventing egress ends of the concrete sections in every case, lbut there 'are many highway engineering departments still employingeth unsealed asphalt filled expansion cracks between concrete sections, and

into which the dowel plate may slide, and for aligning the socket with metal, maybe made out of as light ,steel stock as possible. This greatly decreases the cost of the material, a d it should also be noted that it is not absolutely necessary a purpose of the divisionl plates at the right point.

capable of weakening the concrete to produce the that the dowel plates be continuous from one side of the pavement to the other, as short lengths of dowel plate provided with suitable sockets may be made to perform this function Vjust as well as ay complete continuous length of dowel plate.

' Furthermore, inthe contraction joints it is not absolutely necessary that the division plates be continuous from one side of the pavement, as the here is merely to weaken the concrete so that the crack will form The proper crack will be formed just as well when short lengths of'divislon plates are used, and these short lengths are crack at the Proper point, even though there' are spaces between them where no divisionl plate is present..

Anotheradvantage of the present expansionand contractionyjoin't structures is that the present dowel*V plate and socket arrangement may be manufactured very economically and may therefore oompetewith the dowel rod arrangement of the prior art.' which is a relatively cheap struc- It should alsobe noted that the various elements of the contraction and expansion joints are capable of separate application and do not necessarily have tobe employed in everyv caseinkthe completel combinations shown. Pbrexamplefthe structures for" keeping the concrete sections in alignment'may be-used apart from the nnoftnejomtortneneslble'mlswbeuind of plate need be provided.

the other.

due to me m which the other features of the present joints may be used with advantage in Such joints, even though the flexible metal seals are omitted. In any'case. I prefer to make the parts of the joint symmetrical so that it is only necessary for the 'manufacturer to keep in stock a small number of different parts, and in the most simple types ofthe joints described it will be found that most ofthe parts of the joint may be' ordered directly from the mill in the form of stock which need only be cut to length. I

Referring to Fig. 22, this is another modification inwhich the two concrete sections lll and are separated by a'cont'raction joint of a very simple type. In this case the twoclamping mem, bers |50, |5| may be identical in shape, although 2 it will be noted that the left clamping member will be locateda little higher than the right clamping member ISI, due to ,the thickness of the. horizontal flanges |52, |53 en lthe division plates |54, |55. This difference in height will be taken care of by the sub-grade into which the lower clamping vmember can ber slightly depressed.

In this case the joint includesv the same dowel plate II and the clamping members |50, Iii are similar to those previously described, and in particular to those of Fig. 7. They d iifer slightly in th'e width of the clamping space, since here they are intended merely to clamp a thin sheet metal member |l2 or I5# andthe dowel plate il.

The joint .of Fig. 22 Aay'also be built up of a continuous length of of thevparts or of a plurality of short lengths in all or any one of the parts. In case the -divi'sion plates i, Ill are made of short lengths, they are preferably not overlapped, as it does' not matter if there is a or crack at ,that point just the same."

Each division plate compriseaa vertical portion |54 or Ill and a horlsontal'portion Il! or Ill. u'

. The division plates have their horizontal portions l,

extending in opposite. directionsVthe one being located above and the other below the dowel plate" I3. v".lhulthe division plates may be identicall in shape. structure and sise, so that only one type u horizontal anges |52,

Il prefer to provide the .IIJ with a vertical ange I". altbough itis not absolutely necessary. This vertical danse has-,the advantage that when the division plate is first placed on the dowel plate II the vertical mnge litlocates the division plate properly so that the vertical bodies I, 'Ill are directly one above lIl'urtherlnore, when the clamping member illv is shovedon the combined members Il! anddl the division plate I does not tend to slide with the clamping member, but sits init: proper place. y 'Ihsjointispreferably,butnot .provided with the flexible sheet metal seal vl`l at thetop,whichmay beprovidedwiththebead III, vproviding a' cylinder, each other.

the seal may be bent againl toaprovide a n Eachdependingwall lot outward end'tbeu inward clamping formation `ISI at'the bottom which Iengages the division plate |54. The seal has the usual horizontal ilange |62 with anchoring formations |63.

In this case the division plate |54 is clamped at IBI, and it extends `into the seal only tothe.

point |59.\ Thus, when lthe concrete contracts Pand the seal is drawn apart, the bead |58 may be drawn downward, but the division plate |54 will not have any chance of cuttinguthe seal at |58 because it is spaced from the uppermost part Various forms of clamping members may `be used; as shown, all of which may be shipped in a knocked down condition and assembled very quickly at the job. Most of the parts of the joint are constructed of sheet metal, which lends itself to manufacture by stamping and punching operations, so that it may be constructed at a very low cost. Thefillers, clamping members, copper sealing members, dowel plates, and closure plates may be combined inV various combinations to meet allkinds of diiferent oonditions, asA shownl in the various modifications illustrated.

The present joints are adapted tokeeptlcie`1` adjacent concrete sections in alignment with each other and to transmit load from either Section to the other. They are also adapted to prevent the ingress of foreign material intothe cracks between the concrete sections, whether it'be a contraction jointor an expansion joint, thereby assuring the continuous and efficient operation oiA the joint for a long period oi time.

The' present joints are also so constructed that the parts thereof may be shipped trom the mill as stock materials Without the necessity for. any further operationsexcept the cutting oi these parts to suitable length. The joints are so constructed that there is no chanoeoi the seal becoming damaged by other parts and so that they may be made symmetrically to reduce the number oi different parts.

e ll have illustrated a preferred enibodi` ment of my invention, m modications may be made without departing from the spirit o! the invention, and I do not wish to be limited to the precise details of construction set forth, but desire to avail myself of ali' changes within the scope) of the appended claims.

Having thus described my inventiomwhat I Aclaim. as. new and desire to secure by Letters Patent of the United States,-is:

i. In a joint' for facilitating contraction of sections of concrete in a pavement, the combination of a sliding dowel plate with a division' plate formed with upper and lower body portions and with anV intermediate continuous groove for engaging the dowel plate, and a plurality of clamping members adapted to hold the` walls of said groove in tight engagement with said dowel `plate to assure a close sliding 'fit between the dowel plate and its socket in the concrete pavement, said clamping members comprising stiff 'metal members having a stable supporting surface, an upright portion, and a. pair of parallel flanges engaging the outer walls of the grooved portionvof said division plate. y

2. In a joint for facilitating contraction of sections of concrete in a pavement, the combination of a sliding dowel plate with a division4 plate formed with upper and lower body portions and with an intermediate continuous groove for engaging the dowel plate, and a plurality of clamp'- ing'members adapted to hold the walls of-said groove in tight engagement with said dowel plate to assureva close-sliding t between the dowel plate and its socket inthe concrete pavement, said clamping members-.comprising stiff metal members having' stable supporting surface, an upright portion, and a pair of parallel ilanges engaging the outer walls of the grooved portion oi said ldivision plate, said division` plate being formed in a plurality of overlapping sections whereby the joint may be assembled on the job without the necessityfor cutting any part to length except the dowel plate.

3. I-n a joint for permitting contraction of adjacent concrete sections of pavement, the cbmbination of a division plate formed with an up per portion having a'vertical flange and a hori zontal flange, the latter lflange engaging the top of a dowel plate, the lower section of the divi `sion plate having a horizontal flange and a vertical ilange, the horizontal flange engaging the bottom of the dowel plate, both said sections of division plate having overlapping vertical flanges at the edge of said dowel plate, and a plurality of clamping members-for supporting said division plate and dowel plate, each vclamping member having a stablev supporting surface, a vertical portion, and a clamping portion which vclamps thehorizontal flanges of said, division plate to said dowel plate.

4i. In an expansion ljoint for'concrete, the com- 35 'clamping members for engaging said meansand said dowel plate, each clamping member having an upwardly extending portion, a clamping portion, a foot ange, and. meansfor securing said4 ioot flange to the sub-grade.

t. In an expansion joint ior concrete, the comdowel plate, each clamping member having an upwardly-extending portion, a clamping portion, and a foot ilange, said clamping members being iormed with auxiliary clamping formations at the 'bottom and a sliding closure plate mounted in said auxiliary clamping formations at the bottom of the iointassembly to close the crack between the concrete sections at the bottom.

'7. Inan expansion joint for concrete, the combination of means for forming an expansion space between two adjacent sections of concrete with a sliding dowel plate, a plurality of clamping members for engaging said means and said dowel plate,` each clamping member having an upwardly extending portion, la clamping portion, and a foot flange, said clamping members being oppositelydisposed and engaging the opposite edges of the dowel plate, and a continuous sheet metal socket fox-',oneedge of said dowel plate, having sufficient depth tov receive said dowel `bination, oi means for forming an expansion- 8 plate during the maximum expansion offthe jconcrete sections, said socket being clamped on said dowel plate by said clamping members.

8. In an expansion Joint, the combination of4 crushable means for molding the sections oi' the concrete. pavement with an expansion space,z said crushable means being provided in two sections, one located above and the Lother below a sliding dowel plate, a continuous metal socket for said dowel plate on eachv edge of said dowel plate, and a plurality of clamping lmembers for supporting said expansion Joint in proper position, each of saidl clamping members having a pair oi parallel clamping flanges engaging said socket and forcing its walls into close engagement with thedowel plate, and having upwardly extending portions, and also having a foot ilange for support on the sub-grade.

`9.In a concrete road joint,'the combination er a' slidingl dowel platewich a division plate formed of ilexible sheet metal, material and provided with upper and lower body portions and with an intermediate continuous groove for engaging the dowel plate and clamping means for holding the vwalls of said groove in tight engagement with said dowel plate to assure 'a close sliding t between the dowel plate and -said grooves in the concrete pavement. said clamping members comprising stm metal members provided with means for support of the clamping members, an upright portion and .a pair of oppositely disposed ilanges engasina the outer walls of the ilexible grooved portion of said division platel whereby tight engagement is assured in spite of the inaccuracies of manufacture.

10. In an expansion joint, the combination of crushable meansl for molding sections of concrete pavement to form an expansion` space, a sliding dowel plate, said crushabley means being provided in two sections. one located above, and the other located below said sliding dowel plate, a continuous metal socket on each edge of said dowelplate,.said continuous metal socket contacting the upper and lower surfaces of said sliding dowel plate and having opposing flanges adomos adapted tohold said tion.

11. In an expansion Joint, the combinationv of crushable means for molding the sections of the concrete pavement with an expansion space, said crushable means being provided in twosections, one located above and the other below a sliding dowel plate, a continuous metal socket for saidl dowel plate onJ each edge oi said dowel plate', and a plurality of clamping members for supporting said expansion joint in proper position, each of `said clamping members being of substantially U shape and having its parallel clamping ilanges engaging said socket and forcing its walls into close engagement with the dowel plate.

12. In an end plate structure for concrete Joints, the combination of a sliding end plate with a joint clamping member, said joint clamping member having a stable supporting foot, an

sheath for one edge of' said dowel plate, and a plurality oi' clamping members for supportingsaid dowel plate; said clamping members'each having a vertically extending column, a clamping formation can'ied thereby, and a lower stable supporting ilange for the purpose ot supporting thejoint unit in place for the.pouring of the concrete about it, said clamping members being arranged with said foot flanges extending laterally from said joint unit on' the subgrade at both sidesoi' said Joint unit, said clamping members being arranged with predetermined'of said members on the opposite sides o! said dowel plate whereby the foot-flanges extend in both directions laterally of saidf Joint unit to eifect a rmer supportoi'y said joint unit on the subgra'de for pouring oLconcxete;

lemeansinpcai- .d5 CLIFPRDOIDR 

